Analog phone punch downs

[JOKU]

Hello!

Sorry I Know this may sound very basic to many of you but can someone explain to me the process of replacing an analog phone line in a school? I have been put in charge of managing the phones at my district but have never been trained in telephony. Instead of going to a vendor for help it would be nice if I was able to replace the cable pair instead of paying the money that our district doesn't really have.

An example of an issue I have seen is a teacher's analog phone isn't working. I'v tested the phone in another port and it's working properly. I can find the port on the block that they are using but I don't know what to do after that.

Where do I go from here?

Thanks!

[sms001]

The key to maintaining stuff that old is to remove it VERY carefully, slowly, and attentively. Phone lines aren't terribly complex, and you should be able to figure out what does what as you go along, but PAY ATTENTION; write things down, draw schematics, take pictures. Caveat ~ phone lines carry enough juice to RING A MECHANICAL BELL! So take standard electric work precautions. Also, not everyone who ever ran wire follows standard color coding, so if something is incorrect, it's best to reproduce their work rather than have a mish-mash of conventions at one location.

I looked around, and this and this seem to be extremely basic how-tos. CAUTION! The second page is very badly done, webpage-wise. I think he imported it directly from Geocities.

[Chromatix]

Yeah, standard phone line voltage is 50V - that's basically on the edge of where it starts to be painful and/or dangerous to touch by accident. It's about half the voltage you get on the mains in America - and it's DC, which is more dangerous than the AC you get on the mains.

So treat a live phone line like mains, to be safe.

[Bandit]

And for extra fun, an analogue phone (in North America) rings at 96 volts AC.

It will get your attention - trust me.

Odds are that the jack, or the cord from the phone to the jack has been damaged. It's very rare that the wire in the wall goes bad unless there are renovations.

First step is to replace the cord from the jack to the wall. If that does not work, replace the jack. To replace the jack, make note of the colour codes on the wires and reconnect as required. 99% of the time, you would be connecting the red and green wires in the jack.

Let me know if you have any other questions - I've done this for a few decades.

B

[sms001]

And for extra fun, an analogue phone (in North America) rings at 96 volts AC.
It will get your attention - trust me.

Sure got mine. At the tender age of seven (and this was back in the days when that phone still belonged to Ma Bell) I took ours apart. Was happily poking around the insides and received a shock, similar to the old nine-volt to the tongue. No big whoop I thought... then someone called our house.

Lesson learned. (And pretty cheaply in retrospect.) Now I'm one of those guys who puts lockouts on circuit breakers when I work on runs.